Microsoft has continued its friendship with Apple, announcing it will continue to work on making its products compatible with Apple's.

The software giant's Macintosh Business Unit announced several product updates at the Macworld Conference yesterday including its plans for the upcoming release of the Mac OS X Tiger system. Microsoft executives also said that Office 2004 and Virtual PC sales have been going very well for the company.

"We've sold more copies of Office 2004 in three months of availability than we did in the first six months of Office v. X," Microsoft's Scott Erickson, told MacCentral. "Virtual PC hasn't been out as long, but early signs look very good."

Erickson said that Microsoft has been working closely with Apple to ensure compatibility with the next version of its OS X operating system, expected in the first half of this year. Of particular note is Spotlight, Apple's advanced search technology. Spotlight will index and search Word, Excel and PowerPoint documents - although it will not work with Microsoft's email and information manager, Entourage.

"It won't index Entourage and that's simply due to the way that Spotlight was made versus Entourage," said Erickson. "Entourage saves everything in a database format and we are working with Apple to see how Spotlight can index the database."

Microsoft has also made Entourage compatible with iSync, allowing users to seamlessly sync Entourage to other devices. Erickson said that they have done the work in Entourage to make it a client that will be recognized by iSync. An update for Entourage will be available after Tiger is released.

Erickson said that the Microsoft/Apple relationship is going very well. Not only has the company been working on updates and enhancements announced this week, but it is already hard at work on the next versions of some software, he said.

"Our teams are working on the next versions of Office and Virtual PC," said Erickson. "We will continue to support the Mac and have no plans to stop that. We have the compatibility so customers can work in a cross-platform environment and we have 20 years of making that software for the Mac."